Effects of Eucheuma peptides on platelet aggregation and mouse tail thrombosis induced by carrageenan / 解放军医学杂志

Objective This study is designed to investigate the effect of the peptide from Eucheuma on platelet aggregation and mouse tail thrombosis induced by carrageenan.Methods The peptide was purified from Eucheuma using sephdexG-50 gel chromatography and HPLC.The inhibitory effects of peptide on platelet aggregation induced by adenosine diphosphate (ADP)/thrombin were detected by light transmittance aggregometry.The platelet were treated with normal saline or Eucheuma peptides (2.5,5.0,10.0μg/ml).The platelet aggregation was detected by FLASH continuous spectral fluorescence microplate reader,and the maximum platelet aggregation rate (MAR) was calculated.The peptide (15,30,60mg/kg) and 100mg/kg clopidogrel were intraperitoneal injected into mice for 7 days to confirm the anti-thrombosis activity of the peptide in carrageenan-induced mouse tail thrombosis model.Results The platelet aggregation can be inhibited by the peptide.Comparing the maximum platelet aggregation rate induced by ADP,the results showed that control group was 100％,2.5μg/ml peptide group was 61.84％,5.0μg/ml peptide group was 71.04％ and 10.0μg/ml peptide was 60.95％.The maximum platelet aggregation rate induced by thrombin was also tested.The results showed that control group was 100％,2.5μg/ml peptide group was 75.34％,5.0μg/ml peptide group was 69.96％ and 10.0μg/ml peptide group was 73.74％.The thrombosis rate (2.5μg/ml peptide group was 36.89％,5.0μg/ml peptide group was 17.25％,10.0μg/ml peptide group was 22.99％,and 100mg/kg clopidogrel group was 18.96％,respectively) and the length of thrombus in mice can be reduced by the peptide (15-60mg/kg).Conclusions The carrageenan induced tail thrombosis in mice can be inhibited by the peptide of Eucheuma.It is suggested that the peptide of Eucheuma is a potential compound in anti-thrombosis.

Peptides extracted from eucheuma and their activity against platelet aggregation and bacterial growth / 医学研究生学报

Objective Eucheuma is rich in nutrients and can be an important raw material of food after processed. This study was designed to establish a feasible method of purifying polypeptides from eucheuma and investigate their activity against platelet aggre?gation and bacterial growth. Methods We extracted peptides from eucheuma with acidic solution, detected the effects of different doses of small molecular polypeptide ( 0, 5, 10, 20, and 40μg/mL) on the growth of Escherichia coli ( D1314) and Staphylococcus aureus (s.agr+, RN4220) using the method of turbidity, and analyzed the anti?platelet aggregation activity of the peptides with a whole blood aggregometer. Results The rates of peptides extracted from 50, 100,150, and 200 g of eucheuma were 0.382%, 0.405%, 0.389%, and 0.389%, respectively. The purified sample exhibited a single band on SDS?PAGE. The relative molecular weight of the peptides was about 3kD. The extracted peptides inhibited the growth of Escherichia coli, Staphylococcus aureus, and thrombin?induced platelet aggregation in a dose?dependent manner, with inhibition rates of 44.71%, 51.86%, and 75.00%, respectively. Conclusion The present method can be used to successfully purify low?molecular?weight peptides from eucheuma and effectively inhibit platelet aggre?gation and bacterial growth. The peptides extracted is a potential anti?platelet aggregation agent.

Searching for the best agarose candidate from genus Gracilaria, Eucheuma, Gelidium and local brands

Objective: To explore the potential of local agar of genus Gracilaria, Eucheuma, Gelidium and local brands as an alternative for imported agarose for DNA electrophoresis, and to examine their ability related to separation and migration of DNA fragments in DNA electrophoresis. Methods: Their performance at various concentrations were compared via an experimental study with a specific brand of imported commercial agarose used in molecular biology research. The measured variables were separation and migration during electrophoresis of a DNA fragment. Results: The local agar genus Gracilaria gigas, Gelidium, brand "B" and brand "S" could separate DNA fragments at a concentration between 1% and 2%, with an optimum concentration of 2% w/v, as good as a specific brand of imported commercial agarose. Conclusions: Their performance were very close to that of commercial agarose and can still be improved by further agar purification as well as by pH and sulfur control.

Searching for the best agarose candidate from genusGracilaria,Eucheuma,Gelidium and local brands

Objective:To explore the potential of local agar of genusGracilaria,Eucheuma,Gelidium and local brandsas an alternative for imported agarose forDNA electrophoresis, and to examine their ability related to separation and migration ofDNA fragments inDNA electrophoresis. Methods:Their performance at various concentrations were compared via an experimental study with a specific brand of imported commercial agarose used in molecular biology research. The measured variables were separation and migration during electrophoresis of a DNA fragment. Results: The local agar genusGracilaria gigas,Gelidium, brand B and brand S could separateDNA fragments at a concentration between 1% and 2%, with an optimum concentration of 2% w/v, as good as a specific brand of imported commercial agarose. Conclusions:Their performance were very close to that of commercial agarose and can still be improved by further agar purification as well as by pH and sulfur control.

Preparation of low molecular weight Eucheuma striatum sulfated polysaccharides by oxidative degradation with H_2O_2 under the ultrasonic wave / 中国海洋药物

Objective To prepare low molecular weight Eucheuma striatum sulfated polysaccharides. Methods Eucheuma striatum sulfated polysaccharides were degraded with hydrogen peroxide under the ultrasonic wave. Molecular weight and the content of sulfate radical, 3,6-anhydro-galactose of all sulfated polysaccharides were determined. Results The polysaccharides with molecular weight from 5000 to 40000 were prepared and the content of sulfate radical was above 18.5%. Conclusion This method is fit for preparing low molecular weight and good water-solubility polysaccharides. The post-treatment is simple and the method keeps the sulfated radical perfectly.

Antiviral activities of polysaccharides from Eucheuma gelatinae and Eucheuma striatum in vitro / 中国海洋药物

Objective The antiviral effects of polysaccharides from Eucheuma gelatinae and Eucheuma striatum on herpes simplex virus type 1(HSV-1) and coxsackie virus(CVB3) in vitro were assayed and their antiviral mechanism was elucidated.Methods The antiviral effects of samples were evaluated with cell cytotoxicity by MTT and cytopathic effect(CPE) methods.Antiviral mechanism of two extracts was investigated by four different ways.Results and Conclusion Polysaccharides from Eucheuma gelatinae and Eucheuma striatum had an obviously HSV-1 and CVB3 inhibitory effect.Antiviral activities of two extracts(ESPA and ESPA2) were better than acyclovir(ACV).Antiviral activities of all extracts were better than ribavirin injection.Polysaccharides from Eucheuma striatum had remarkable anti-CVB3 effects.The experiment also showed that Eucheuma polysaccharides not only kill the above viruses directly but also restrain them via getting into cells or absorbing on cells.

THE NUTRITIONAL VALUE AND THE EDIBLE SAFETY OF FASTFOOD EUCHEUMA / 营养学报

Objective:The nutritional value and edible safety were evaluated for fastfood Eucheuma. Methods:The nutritional composition and the contents of heavy metal element and microbiology index were tested, and the test of acute toxicity and mutation were performed to evaluate the nutritional value and edible safety. Results:The main components of fastfood Eucheuma were dietary fibre and mineral components, and the contents of protein and fat were very low. The gross content of dietary fibre was 88.6%. The contents of Zn and Ca were the highest among the mineral components.The index of heavy metal elements and microbes(cfu) were lower than that of the national standard. It was non-toxic and non-mutagenic. Conclusion:The fastfood Eucheuma is a functional food, and also a safe food of new resource.